Question: $-3\dfrac{1}{2} \div \left(-1\dfrac{2}{5}\right) = $
Answer: Let's start by converting the mixed numbers to fractions. $\phantom{=}-3\dfrac{1}{2} \div \left(-1\dfrac{2}{5}\right)$ $=-\dfrac{7}{2}\div\left(-\dfrac{7}{5}\right)$ $=-\dfrac{7}{2}\cdot\left(-\dfrac{5}{7}\right) ~~~~~~~\text{multiply by the reciprocal}$ $=\dfrac{35}{14}$ $=\dfrac{5}{2} \text{ or }2\dfrac12$